The present invention relates to oil return structures for vehicle drive apparatuses.
There exists a vehicle drive apparatus where the entire vehicle drive apparatus is structured compactly by forming an opening on the bottom portion of a case that houses the automatic transmission, which serves as an oil supply target device, disposing a hydraulic control apparatus under the automatic transmission such that the upper side thereof is inserted inside the case from the opening in the bottom portion of the case, and installing an oil pan such that the hydraulic control apparatus is covered from below (refer, for example, to Japanese Patent Application Publication No. JP-A-2005-344938).
In the structure described above, the oil that has been retained in the oil pan is drawn up by an oil pump and fed to the hydraulic control apparatus. In addition, in the hydraulic control apparatus, the flow of the oil is switched, the pressure of the oil is adjusted, and a portion of the oil is supplied to each of the friction engaging elements of the transmission as operating oil. In addition, the remaining oil is supplied to, for example, the support bearings and the rotating elements of the transmission for the lubricating and cooling thereof. In addition, the oil for lubricating and cooling that has been supplied to the transmission flows down over the inner surface of the case toward the bottom portion of the case, and then returns to the oil pan from the opening that is formed in the bottom portion thereof.